This is a 371 of PCT/IB00/00588 filed May 8, 2000.
The present invention relates to novel tetrazolinone derivatives, to processes for their preparation and to their use as herbicides.
In Japanese Laid-Open Patent Publications No. 82258/1995, No. 97372/1995 and No. 118246/1995 there are disclosed preparation processes of some tetrazolinone derivatives and a preparation process of 1-substituted-5(4H)-tetrazolinones, the intermediates thereof. Moreover, the EP-A-146,279 discloses that some tetrazolinone derivatives have herbicidal activities.
However, the known tetrazolinone derivatives are not fully satisfactory with regard to their herbicidal activity and their phytotoxicity against crops.
According to the invention there have now been found novel tetrazolinone derivatives of the general formula (I) 
wherein
R1 represents methyl or ethyl,
R2 represents halogen, alkyl, haloalkyl, alkoxy, haloalkoxy, alkylthio, haloalkylthio, alkylsulfinyl, alkylsulfonyl, phenyl, phenoxy, alkoxycarbonyl, nitro or cyano, and n represents 0, 1, 2, 3, 4 or 5.
The compounds of the formula (I), according to the invention, can be obtained by a process in which
a) compounds of the general formula (II) 
xe2x80x83wherein
R1 is defined as mentioned above, are reacted with compounds of the general formula (III) 
xe2x80x83wherein
R2 and n are defined as mentioned above, and
M represents a leaving group such as chloro or bromo
in the presence of an inert solvent and, if appropriate, in the presence of a base.
The compounds of the formula (I) of the present invention posses strong herbicidal activities and especially demonstrate an excellent herbicidal effect compared with the known compounds described in the aforementioned EP-A-146,279 which are similar to the compounds of the formula (I). The compounds of the invention nevertheless also show a good compatibility with crops. Therefore, the compounds of the present invention can be potentially employed as agrochemicals, specifically as herbicides.
In the formulae mentioned above:
Halogen in xe2x80x9chalogenxe2x80x9d, xe2x80x9chaloalkylxe2x80x9d, xe2x80x9chaloalkoxyxe2x80x9d and xe2x80x9chaloalkylthioxe2x80x9d represents fluoro, chloro, bromo or iodo, and preferably fluoro, chloro or bromo.
xe2x80x9cAlkylxe2x80x9d may be straight chain or branched chain and there may be mentioned, for example, methyl, ethyl, n- or iso-propyl, n-, iso-, sec- or tert-butyl, n- or iso-pentyl, tert-amyl, pentan-3-yl, neopentyl and n-hexyl.
xe2x80x9cAlkoxyxe2x80x9d may be straight chain or branched chain and there may be mentioned, for example, methoxy, ethoxy, propoxy, isopropoxy, n-, iso-, sec- or tert-butoxy, n-pentyloxy and n-hexyloxy.
xe2x80x9cAlkylthioxe2x80x9d may be straight chain or branched chain and there may be mentioned, for example, methylthio, ethylthio, n-propylthio, isopropylthio and n-butylthio.
xe2x80x9cAlkylsulfinylxe2x80x9d may be straight chain or branched chain and there may be mentioned, for example, methylsulfinyl, ethylsulfinyl, n-propylsulfinyl, isopropylsulfinyl and n-butylsulfinyl.
xe2x80x9cAlkylsulfonylxe2x80x9d may be straight chain or branched chain and there may be mentioned, for example, methylsulfonyl, ethylsulfonyl, n-propylsulfonyl, isopropyl-sulfonyl and n-butylsulfonyl.
xe2x80x9cHaloalkylxe2x80x9d may be straight chain or branched chain and there may be mentioned, for example, difluoromethyl, trifluoromethyl, 2-fluoroethyl, 2-chloroethyl, 2-bromoethyl, 2,2,2-trifluoroethyl, 1,1,2,2-tetrafluoroethyl, 1,1,2,2,2-pentafluoroethyl, 2,2,3,3,3-pentafluoropropyl, 3-chloropropyl, 1,3-difluoropropan-2-yl, 1,1,1-trifluoropropan-2-yl, 2,2,3,3,4,4,4-heptafluorobutyl and 3-bromopropyl.
The Haloalkyl part of xe2x80x9chaloalkoxyxe2x80x9d and xe2x80x9chaloalkylthioxe2x80x9d may be as defined in the above-mentioned xe2x80x9chaloalkylxe2x80x9d.
As xe2x80x9calkoxycarbonylxe2x80x9d there may be mentioned, for example, methoxycarbonyl, ethoxycarbonyl, n-propoxycarbonyl, isopropoxycarbonyl and n-butoxycarbonyl.
As a preferable group of compounds of the present invention there can be mentioned the compounds of the aforementioned formula (I) wherein
R1 represents methyl or ethyl,
R2 represents fluoro, chloro, bromo, C1-4 alkyl, C1-4 haloalkyl, C1-4 alkoxy, C1-4 haloalkoxy, C1-4 alkylthio, C1-4 haloalkylthio, C1-4 alkylsulfinyl, C1-4 alkylsulfonyl, phenyl, phenoxy, C1-4 alkoxycarbonyl, nitro or cyano, and n represents 0, 1, 2, 3 or 4.
As a more preferable group of compounds of the present invention there can be mentioned the compounds of the aforementioned formula (I) wherein
R1 represents methyl,
R2 represents fluoro, chloro, methyl, ethyl, n-propyl, isopropyl, tert-butyl, trifluoromethyl, methoxy, ethoxy, isopropoxy, trifluoromethoxy, difluoromethoxy, 2,2,2-trifluoroethoxy, methylthio, ethylthio, isopropylthio, methysulfinyl, methylsulfonyl, phenyl, phenoxy, methoxycarbonyl, ethoxycarbonyl, nitro or cyano, and n represents 0, 1, 2, or 3.
Among the compounds of the aforementioned formula (I) there may be especially pointed out the compounds which are represented by the following formula 
wherein the carbon atom marked with * represents an asymmetric carbon atom and R1 and R2 have the same meaning as mentioned above. Based on this fact the compounds of the present invention can exist as pure optically active enantiomers or in a form of optional mixtures of optically active enantiomers. Therefore, the compounds of the aforementioned formula (I) of the present invention include optically active substances and mixtures thereof.
Using, for example, 1-((S)-xcex1-methylbenzyl)-5(4H)-tetrazolinone and N-isopropyl-N-phenylcarbamoyl chloride as the starting materials according to preparation process a), the said preparation process can be illustrated by the following reaction scheme: 
The compounds of the formula (II), which are used as the starting materials in the aforementioned preparation process a) are novel compounds, which were not described in literature, and can be prepared, for example, by the following proccesses in which
according to process variant b) compounds of the general formula (IV) 
xe2x80x83wherein
R1 is defined as mentioned above,
are reacted with trimethylsilyl azide in the presence of a catalytic amount of boron trifluoride-ether-complex, or
according to process variant c) compounds of the above-mentioned general formula (IV) are reacted with sodium azide in a polar solvent in the presence of a catalytic quantity of aluminium chloride.
The compounds of the general formula (IV) which are used as the starting material in the above-mentioned preparation process variants b) and c) include isocyanates known in the area of organic chemistry and can be easily obtained, for example, by reacting amines of the general formula (V) 
wherein
R1 is as defined above,
with, for example, phosgene according to known methods described, for example, in xe2x80x9cSHIN JIKKEN KAGAKU KOUZAxe2x80x9d (New experimental chemistry lecture) Vol. 14, III, pp.1490-1496 (published by Maruzen Ltd. on Feb. 20, 1978).
The compounds of the above-mentioned formula (V) can be synthesized, for example, similarly to the methods described in xe2x80x9cSHIN JIKKEN KAGAKU KOUZAxe2x80x9d (New experimental chemistry lecture) Vol. 14, III, pp.1332-1398 (published by Maruzen Ltd. on Feb. 20, 1978) or Organic Reactions, Vol. 5, 1949, 301-330 (John Wiley and Sons, Inc.).
As compounds of the above-mentioned formula (II) there can be mentioned the following species:
1-((S)-xcex1-methylbenzyl)-5(4H)-tetrazolinone,
1-((R)-xcex1-methylbenzyl)-5(4H)-tetrazolinone,
1-((S)-xcex1-ethylbenzyl)-5(4H)-tetrazolinone,
1-((R)-xcex1-ethylbenzyl)-5(4H)-tetrazolinone.
The compounds of the formula (III) to be reacted with the compounds of the above-mentioned formula (II) include N-isopropyl-N-(substituted)phenylcarbamoyl halides which are well known in the area of organic chemistry. As typical examples of them there can be mentioned the following compounds:
N-isopropyl-N-phenylcarbamoyl chloride,
N-isopropyl-N-(4-fluorophenyl)carbamoyl chloride,
N-isopropyl-N-(3-methylphenyl)carbamoyl chloride,
N-isopropyl-N-(4-trifluoromethylphenyl)carbamoyl chloride,
N-isopropyl-N-(2-ethoxyphenyl)carbamoyl chloride,
N-isopropyl-N-(4-difluoromethoxyphenyl)carbamoyl chloride,
N-isopropyl-N-(4-isopropylthiophenyl)carbamoyl chloride,
N-isopropyl-N-(4-methylsulfinylphenyl)carbamoyl chloride,
N-isopropyl-N-(4-methylsulfonylphenyl)carbamoyl chloride,
N-isopropyl-N-(4-2,2,2-trifluoroethylthiophenyl)carbamoyl chloride,
N-isopropyl-N-(4-phenylphenyl)carbamoyl chloride,
N-isopropyl-N-(3-phenoxyphenyl)carbamoyl chloride,
N-isopropyl-N-(2-ethoxycarbonylphenyl)carbamoyl chloride,
N-isopropyl-N-(4-nitrophenyl)carbamoyl chloride,
N-isopropyl-N-(4-cyanophenyl)carbamoyl chloride and the bromides corresponding to these chlorides.
The reaction of the preparation process a) is usually conducted in an inert organic solvent. As examples of such inert organic solvents there can be mentioned aliphatic, alicyclic and aromatic hydrocarbons (which may optionally be chlorinated), for example, pentane, hexane, cyclohexane, petroleum ether, ligroine, benzene, toluene, xylene, dichloromethane, chloroform, carbon tetetrachloride, 1,2-dichloroethane, chlorobenzene, dichlorobenzene; ethers, for example, diethyl ether, methyl ethyl ether, diisopropyl ether, dibutyl ether, dioxane, dimethoxyethane (DME), tetra-hydrofuran (THF), diethylene glycol dimethyl ether (DGM); nitriles, for example, acetonitrile, propionitrile; acid amides, for example, dimethylformamide (DMF), dimethylacetamide (DMA), N-methylpyrrolidone, 1,3-dimethyl-2-imidazolidinone, hexamethylphosphoric triamide (HMPA).
The preparation process a) may be conducted in the presence of a base, preferable in the presence of the base 4-dimethylaminopyridine (DMAP).
In case of using DMAP as a base, the reaction of the preparation process a) is usually conducted at about xe2x88x9210 to about 200xc2x0 C., preferably about 25 to about 140xc2x0 C. under normal pressure. Optionally it is possible to conduct the reaction under elevated pressure or under reduced pressure.
Moreover, it is possible to conduct the reaction of the preparation process a) using other bases than DMAP. As such bases there can be mentioned inorganic salts (for example, sodium carbonate, potassium carbonate etc.), alkyl alcoholates (for example, sodium methoxide, sodium ethoxide, potassium tert-butoxide), sodium hydroxide, potassium hydroxide, lithium hydroxide, organic bases (for example, triethylamine, 1,1,4,4-tetramethylethylenediamine, N,N-dimethylaniline, pyridine etc.).
In case of conducting said reaction using these bases, the compounds of the formula (I) can be selectively obtained by using DMAP as a catalyst.
The reaction temperature in this case may be in the range of usually about 0 to about 150xc2x0 C., preferably about 25 to about 100xc2x0 C. Said reaction is conducted desirably under normal pressure. Optionally, however, it is possible to conduct it under elevated pressure or under reduced pressure.
The desired compounds of the formula (I), according to the present invention, can be obtained, for example, by reacting 1 mole of a compound of the formula (II) with about 1 mole to about 1.5 moles of a compound of the formula (III) in the presence of about 1 mole to about 1.5 moles of DMAP as a base and in such an inert solvent as mentioned above. The compounds of the formula (I) can also be prepared by reacting 1 mole of a compound of the formula (II) with about 1 mole to about 1.5 moles of a compound of the formula (III) in the presence of about 0.01 mole to about 0.3 moles of DMAP as a catalyst and, for example, about 1 mole to about 1.5 moles of potassium carbonate as a base and in an inert solvent of the kind as mentioned above.
The compounds of the formula (I), according to the present invention thus obtained can be isolated and purified, for example, by means of crystallization, chromatography etc.
The reaction of the aforementioned preparation process b) can be conducted using a boron trifluoride-ether-complex as a catalyst. The reaction temperature is usually kept at about 0 to about 200xc2x0 C., preferably about 50 to about 150xc2x0 C. The reaction may be conducted desirably under normal pressure. Optionally, however, it is possible to conduct it under elevated pressure or under reduced pressure.
The preparation process b) is usually conducted by reacting 1 mole of a compound of the formula (IV) with about 1 mole to about 2 moles of trimethylsilyl azide in the presence of about 0.005 moles to about 0.01 mole of boron trifluoride-ether-complex as a catalyst.
The reaction of the preparation process c) is usually conducted in a polar solvent. As such polar solvent there can be mentioned, for example, acid amides such as dimethylformamide, dimethylacetamide and sufoxides such as dimethylsulfoxide, sulfolane. The reaction temperature may be generally about 0 to about 200xc2x0 C., preferably about 20 to about 150xc2x0 C. The reaction may be conducted desirably under normal pressure. Optionally, however, it is possible to conduct it under elevated pressure or under reduced pressure.
The preparation process c) can be conducted by reacting 1 mole of a compound of the formula (IV) with about 1 mole to about 1.5 moles of sodium azide in the presence of about 0.05 moles to about 1 mole of aluminum chloride as a catalyst and in a polar solvent, for example, dimethylformamide.
The compounds of the formula (I), according to the present invention, have, as shown in the test examples to be described later, excellent herbicidal activities and can be used as herbicidal agents for controlling weeds. xe2x80x9cWeedsxe2x80x9d in this regard mean, in the broadest sense, all plants which grow in locations where they are undesired.
The compounds, according to the present invention act as total or selective herbicides depending upon the applied concentration. The active compounds of the present invention can be used, for example, as selective herbicides between the following weeds and cultures.
Dicotyledon weeds of the genera: Sinapis, Lepidium, Galium, Stellaria, Chenopodium, Urtica, Senecio, Amaranthus, Portulaca, Xanthium, Ipomoea, Polygonum, Ambrosia, Cirsium, Sonchus, Solanum, Rorippa, Lamium, Veronica, Datura, Viola, Galeopsis, Papaver, Centaurea, Galinsoga, Rotala, Lindemia etc.
Dicotyledon cultures of the genera: Gossypium, Glycine, Beta, Daucus, Phaseolus, Pisum, Solanum, Linum, Ipomoea, Vicia, Nicotiana, Lycopersicon, Arachis, Brassica, Lactuca, Cucumis, Cucurbita etc.
Monocotyledon weeds of the genera: Echinochloa, Setaria, Panicum, Digitaria, Phleum, Poa, Festuca, Eleusine, Lolium, Bromus, Avena, Cyperus, Sorghum, Agropyron, Monochoria, Fimbristylis, Sagittaria, Eleocharis, Scirpus, Paspalum, Ischaemum, Agrostis, Alopecurus, Cynodon etc.
Monocotyledon cultures of the genera: Oryza, Zea, Triticum, Hordeum, Avena, Secale, Sorghum, Panicum, Saccharum, Ananas, Asparagus, Allium etc.
According to the invention all plants and plant parts can be treated. The term plants includes all plants and plant populations, such as desired or undesired wild plants and cultivated plants (including naturally occurring cultivated varieties). Cultivated plants can be plant varieties that were obtained by conventional bredding and optimizing processes or by biotechnological and genetic engineering methods or a combination of such processes and methods, including transgenic plants and including plant varieties that cannot or can be protected by plant patents or plant variety rights. Plant parts are all parts and organs of plants occurring above or below the surface of the soil, e.g. shoots, leaves, needles, stalks and stems, trunks, flowers, fruits and seeds as well as roots, tubers, bulbs and rhizomes. The term plant parts also includes harvested crops and propagation material, e.g. cuttings, tubers, bulbs, rhizomes, shoots and seeds.
According to the invention the plants and plants parts are treated using the usual methods by applying the active ingredients or compositions containing them directly to the plants or plant parts or to their surroundings (including the soil) or storeroom, e.g. by dipping, spraying, dusting, fogging, spreading and in the case of propagation material also by coating using one or multiple layers.
The use of the compounds of the formula (I), according to the present, invention is not restricted to the above-mentioned plants, but may be applied to other plants in the same manner. The active compounds can, depending upon the applied concentration, non-selectively control weeds and may be used, for example, on industrial terrain, rail tracks, paths, places with or without planted trees.
Moreover, the compounds, according to the present invention, can be used for controlling weeds in perennial cultures and applied in, for example, afforestations, decorative tree plantings, orchards, vineyards, citrus groves, nut orchards, banana plantations, coffee plantations, tea plantations, rubber plantations, oil palm plantations, cocoa plantations, soft fruit plantings, hopfields etc. and can be applied for the selective controlling of weeds in annual cultures.
The compounds of the formula (I), according to the present invention, can be made into customary agrochemical formulations for their application. As such formulations there can be mentioned,-for example, solutions, emulsions, wettable powders, suspensions, powders, soluble powders, granules, tablets, suspension-emulsion concentrates, microcapsules in polymeric substances, jumbo formulations etc.
The formulations can be prepared according to known methods, for example, by mixing the compounds of the formula (I) of the present invention with extenders, namely liquid diluents and/or solid diluents or carriers, optionally with surface-active agents, namely emulsifiers and/or dispersants and/or foam-forming agents. When water is used as an extender, for example, organic solvents can be used as auxiliary solvents.
As liquid diluents or carriers there can be mentioned aromatic hydrocarbons (for example, xylene, toluene, alkylnaphthalene etc.), chlorinated aromatic or chlorinated aliphatic hydrocarbons (for example, chlorobenzenes, ethylene chlorides, methylene chloride etc.), aliphatic hydrocarbons [for example, cyclohexane etc. or paraffins (for example, mineral oil fractions etc.)], alcohols (for example, butanol, glycols and their ethers and esters etc.), ketones (for example, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone etc.), strongly polar solvents (for example, dimethylformamide, dimethylsulphoxide etc.) and water.
As solid diluents there can be mentioned, for example, ground natural minerals (for example, kaolin, clay, talc, chalk, quartz, attapulgite, montmorillonite, diatomaceous earth etc.), ground synthetic minerals (for example, highly dispersed silicic acid, alumina, silicates etc.) etc.
As solid carriers for granules there can be mentioned, for example, crushed and fractionated rocks (for example, calcite, marble, pumice, sepiolite, dolomite etc.), synthetic granules of inorganic and organic meals, particles of organic materials (for example, sawdust, coconut shells, maize cobs and tobacco stalks etc.) etc.
As emulsifiers and/or foam-forming agents there can be mentioned nonionic and anionic emulsifiers [for example, polyoxyethylene fatty acid esters, polyoxyethylene fatty acid alcohol ethers (for example, alkylaryl polyglycol ethers, alkylsulphonates, alkylsulphates, arylsulphonates etc.)], albumin hydrolysis products etc.
As dispersants there are included, for example, ligninsulphite waste liquor and methyl cellulose.
Tackifiers may also be used in the formulations (powders, granules, emulsions). As usable tackifiers there can be mentioned, for example, carboxymethyl cellulose, natural and synthetic polymers (for example, gum arabic, polyvinyl alcohol, polyvinyl acetate etc.).
Colorants may also be used. As said colorants there can be mentioned, for example, inorganic pigments (for example, iron oxide, titanium oxide, Prussian Blue etc.), organic dyestuffs such as alizarin dyestuffs, azo dyestuffs or metal phthalocyanine dyestuffs, and further trace nutrients such as salts of metals such as iron, manganese, boron, copper, cobalt, molybdenum, zinc etc.
Said formulations can contain in a range of generally 0.1-95% by weight, preferably 0.5-90% by weight of the compounds of the aforementioned formula (I).
The compounds of the formula (I) of the present invention can be used as such or in their formulated forms for controlling weeds. They can be used also as a mixed composition with known herbicides. Such a mixed composition can be previously prepared as a final formulation form or can be prepared by tank-mixing on the occasion of the application.
The compounds of the formula (I) of the present invention can be used also with a safener and their application as a selective herbicide may be broadened by such a mixing. As an example of such safener 1-(xcex1,xcex1-dimethylbenzyl)-3-p-tolylurea can be mentioned.
As herbicides, which can be combined with the compounds of the formula (I) of the present invention there can be mentioned, for example, the following known herbicides:
4-amino-6-(1,1-dimethylethyl)-3-ethylthio-1,2,4-triazin-5(4H)-one, 1-amino-6-ethylthio-3-(2,2-dimethylpropyl)-1,3,5-triazin-2,4(1H,3H)-dione, or N-(2-benzothiazolyl)-N,Nxe2x80x2-dimethylurea etc. (eg. for controlling weeds in cereal cultures);
4-amino-3-methyl-6-phenyl-1,2,4-triazin-5(4H)-one etc. (e.g. for controlling weeds in sugar cane cultures);
4-amino-6-(1,1-dimethylethyl)-3-methylthio-1,2,4-triazin-5(4H)-one etc. (e.g. for controlling weeds in soybean cultures);
methyl xcex1-(4,6-dimethoxypyrimidin-2-ylcarbamoylsulfamoyl)-o-toluate etc. (e.g. for controlling weeds in paddy rice culture).
Surprisingly, some of these herbicidal combinations of these herbicides with compounds of the formula (I) of the present invention show synergistic effects.
Compounds of the formula (I) of the present invention can be applied directly as such or in formulated forms such as ready-to-use solutions, emulsions, suspensions, powders, granules or used in the use forms prepared by further dilution.
The compounds of the formula (I) of the present invention can be applied by means of, for example, watering, spraying, atomizing, dusting or granule application etc.
The compounds of the formula (I) of the present invention can be used at any stages before and after germination of plants. They may also be mixed into the soil before sowing.
The application rate of the compounds of the formula (I) of the present invention may be varied in a substantial range and is fundamentally different according to the nature of the desired effect. In case of herbicidal use, as a suitable application rate there can be mentioned, for example, a range of about 0.01 to about 5 kg, preferably about 0.1 to about 3 kg of the compounds of the formula (I) of the present invention per hectare.